HOW TO 

GONSERVE MATERIAL 


BY 

HARRISON E. HOWE 

LECTURE No. 30 
OF THE 

FACTORY MANAGEMENT 
COURSE AND SERVICE 



Volume 8, Lecture 2 


INDUSTRIAL EXTENSION INSTITUTE 

INCORPORATED 

NEW YORK 


Collected set. 






HOW TO 

CONSERVE MATERIAL 


BY 

HARRISON E? HOWE 

#' 

LECTURE No. 30 
OF THE 

FACTORY MANAGEMENT 
COURSE AND SERVICE 


9 

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Volume 8, Lecture 2 


INDUSTRIAL EXTENSION INSTITUTE 

INCORPORATED 

NEW YORK 



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JUl 12 1922 


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After graduation from Earlham College in 1901, Mr. 
Howe was a student in the Graduate School at the 
University of Michigan. When the Sanilac Sugar Re¬ 
fining Company was formed he became chemist for that 
enterprise, leaving in 1904 to join the staff of the 
Bausch and Lomb Optical Company, where he served in 
various capacities, including that of Chief Chemist, until 
1916. Meanwhile the degree of M.S. was earned at the 
University of Rochester. From 1916 to 1919 he was a 
member of the staff of Arthur D. Little, Incorporated; 
serving for more than a year as the assistant to the 
President of the Canadian corporation, Arthur D. Little, 
Limited, where he devoted himself to the study of com¬ 
mercial utilization of natural resources. During the lat¬ 
ter part of the war Mr. Howe served in the Nitrate 
Division of Army Ordnance and is now Chairman of the 
Division of Research Extension, National Research Coun¬ 
cil. Throughout his professional career he has special¬ 
ized in the application of science to industry. For some 
years a member of the American Chemical Society, Mr. 
Howe has served as Chairman of the Division of Indus¬ 
trial and Engineering Chemistry. He is now Secretary 
of that Division, Counsellor-at-large of the Society, and 
a member of its Advisory Committee. He is also a mem¬ 
ber of the American Institute of Mining and Metallurgi¬ 
cal Engineers and at various times has been active in 
manv other scientific and technical societies. 

In this lecture, Mr. Howe shows broadly how, through 
the application of scientific control, material may be 
conserved by reducing rejections; by the selection of 
proper material; by the introduction of new methods, 
new equipment, or new material; by the utilization and 
prevention of waste, and by reclamation or salvage 
methods. ' 
























































































































HOW TO CONSERVE MATERIAL 


By HARRISON E. HOWE 

Applied Salvage.—Among the many pastimes and 
hobbies which have been developed on a paying basis 
I have always been struck with the success of an 
Irishman who began to raise ducks in one of the small 
smelter settlements of the west; in fact he became so 
much concerned with raising ducks that he gave up 
his job in the mine and smelter and devoted his entire 
time to this peaceful occupation. He had gone to the 
superintendent with the story that while he enjoyed 
his work underground and elsewhere about the plant 
he was after all a simple minded fellow who delighted 
most in raising ducks. He might be a wonderful 
workman in other respects, but when it came to rais¬ 
ing ducks he acknowledged no one as his equal. His 
experience was supposed to have dated from the days 
in old Ireland, and at length he was granted permis¬ 
sion to put up a little dam across a gully and have 
certain mine waters diverted there to provide a suit¬ 
able pond for his beloved ducks. This the superin¬ 
tendent was glad to grant after hearing his story, but 
by and by the growing wealth of the Irishman became 
so apparent that curiosity was aroused. It was found 

Copyright, 1920, The Industrial Extension Institute, Inc., New York. 

3 



4 


HOW TO CONSERVE MATERIAL 


that he was not so simple minded as he had claimed 
to he—by placing strips of iron in his duck pond he 


had been able to recover from the waste waters quan¬ 
tities of copper which, thus salvaged, had become the 
foundation stone of a fortune, which was rapidly 
growing. The ducks cannot be called decoys, but they 
certainly provided an excellent camouflage. 

There are many instances of such wastes, the pre¬ 
vention and utilization of which plays such an im¬ 
portant part in industrial conservation. Many of our 
industrial research laboratories devote their time to 
the study of wastes, and much of our academic re¬ 
search has somewhere in the future the possibility 
that the results may effect some economy in production. 

Science an Aid in Conservation. —I think it would 
be proper to define industrial conservation as any 
method, plan or arrangement which effects economies 
either in raw materials, in labor or in overhead man¬ 
agement. It all comes to the valuation of time and 
materials, which are the two great divisions making 
up the cost of manufacture and distribution. In this 
discussion I would like to emphasize how potent is 
applied science in affecting such conservation, and as 
no special problem is before us we can best argue the 
possibilities from what the past has shown us to be 
possible. If, as a result, you may be convinced that 
science applied in the proper direction in whatever 
industry you may be interested will enable you to 
make substantial progress, then the object of this dis¬ 
cussion will have been accomplished. 

Most men are agreed that if science is to have the 
greatest possible earning power for an industry, in- 



HOW TO CONSERVE MATERIAL 


5 


dustry must make its scientific department an inti¬ 
mate, integral, internal part of its organization. In 
visiting the laboratories of numerous industries in the 
past I have often been struck with the lack of suitable 
facilities for attacking the problems which have been 
put up to the men in charge. Perhaps the superin¬ 
tendent or someone in authority has been convinced 
that they ought to do something along scientific lines 
and have set out to find some unoccupied corner that 
could be washed, provided with running water and 
gas, a table or two, and called a laboratory. It is 
wonderful how much men have accomplished amid 
such poor surroundings, and one can pay a tribute to 
their courage and optimism in carrying on research 
under such circumstances in a way that has won for 
them recognition in the organization and brought 
them suitable quarters in which to pursue their work. 

Many manufacturers have only turned to scientific 
men when in trouble, just as we as individuals usually 
call upon a physician after we have been ill for some 
time and much advertised remedies have failed to 
effect a cure. It may be better to follow the Chinese 
plan and pay our physicians only when we are in good 
health. At all events the commercial laboratory has 
found an important field for its activities, being avail¬ 
able in a consulting capacity upon troubles which 
arise in the plant and which those in the plant have 
been unable to solve. This fact alone indicates that 
they are not easy, and manufacturers do not always 
display the patience and faith that may rightfully be 
expected in the ultimate outcome when they place 
their work in the hands of a consultant. 


6 


HOW TO CONSERVE MATERIAL 


Another one of the favorite plans is that of support¬ 
ing a student, by means of a Fellowship, in a college 
or university, where he has the benefit of expert di¬ 
rection and where library facilities are available as 
well as the opportunity of rubbing elbows with scien¬ 
tists in other fields. There are abundant illustrations 
of wonderful achievements which have followed a sort 
of cross pollonization of the sciences. Frequently a 
man working in a given field will find a colleague 
engaged upon a problem quite unlike his own, yet 
having devised some special method or apparatus 
which fits in exactly with the solution of his own diffi¬ 
culties. 

Still another method is the cooperative one where 
those having common interests pool their resources 
and support a laboratory, the results of which are 
made available to all the members of the Association. 
These Associations have served actually to elevate 
whole industries and, contrary to the expectations of 
some of the members, has rarely changed the relative 
positions of the leaders and the others composing the 
Association. Thus, in the Association engaged in im¬ 
proving malleable iron those whose product formerly 
had the greatest strength and uniformity still excel in 
these particulars, but at the same time the product of 
all members of the Association has been improved 
much to the benefit of the leaders as well as the others 
in that field of endeavor. 

Where the Laboratory Helps. —But whatever method 
may be followed in applying science to effect indus¬ 
trial conservation the expense may seem large to those 
who have not had an opportunity to realize upon such 


HOW TO CONSERVE MATERIAL 


7 


an investment, and it is well, therefore, to indicate 
some of the things that have been accomplished. 

In Reducing Costs. —One of the less spectacular 
of the accomplishments is something that occurs every 
day and has to do with the use of the laboratory in 
securing the right materials to be used in manufac¬ 
ture. In many instances the cost of raw materials is 
quite insignificant as compared to the other costs that 
make up the total, such as the labor item. Anything 
that will ensure a decrease in the percentage of sec¬ 
onds that are inadvertentlv manufactured, or will 
guarantee that the finished product will have the de¬ 
sired characteristics, is obviously important. A strik¬ 
ing example may be drawn from the automobile field 
where we have been taught that vanadium steel is 
largely used because of its great strength and ability 
to resist shock. It has these characteristics to a 
marked degree, but as compared with high carbon 
steel, which also has great strength, it possesses 
machineability, which makes it possible to work 
vanadium steel by ordinary methods. High carbon 
steel requires grinding and other expensive operations, 
so that a given automobile part which costs, finished, 
about $6.00 when made of vanadium steel, costs more 
than $13.00 if high carbon steel is employed. The 
result is practically the same. The difference is due 
to labor charges. The saving is made by choosing 
materials, with the help of the laboratory, which are 
the most desirable for the purpose. 

In Minimizing Rejections. —A case once came to my 
notice where a certain part was being made of a steel 
either improperly chosen for the service to be per- 


8 


HOW TO CONSERVE MATERIAL 


formed or subjected to unsuitable treatment in pre¬ 
paring the machined part, by heat treating, for its life 
work. These bits of metal were very small; in fact 
they were rollers of certain bearings. As made in 
that plant the labor charge against them was high; 
but because the whole process lacked suitable scien¬ 
tific control, approximately 60 per cent of the rollers, 
after all the work had been done upon them, failed 
and had to be discarded. Even those which came 
through sufficiently perfect for assembling could not 
be depended upon to stand up against any service. 
At last accounts this concern had not yet been con¬ 
vinced that a few dollars spent in scientific work 
would not only save them many dollars, but would be 
a guarantee against the failure of their product in 
use. 

Contrasted with this is the case of a manufacturer 
who had a contract for a U-shaped metal piece used 
in the manufacture of an item of military equipment. 
These small pieces required to be case hardened after 
they were formed, and early in his work as high as 
70 per cent of these pieces were discarded as useless 
because in the heat treatment they twisted and warped 
out of shape. This manufacturer, having had occasion 
before to call in a scientist, procured the services of 
an experienced metallurgist, who soon found the seat 
of the trouble and was successful in prescribing a 
remedy and in bringing up the percentage of accept¬ 
able pieces to more than 98 per cent. Indeed the re¬ 
sults were so satisfactory that this plant thereafter 
received all the orders for the part in question. 

Instances of this sort are not confined to the manu- 


HOW TO CONSERVE MATERIAL 


9 


factures of small metallic articles. In one plant there 
were tons of steel billets rejected by inspectors be¬ 
cause of imperfections that were only eliminated when 
science was given an opportunity to be of service. 

Conservation Hinges Upon Research. —It must be 
recalled, however, that often savings which seem ap¬ 
parently easy to make in the light of our present 
knowledge were impossible until some of the funda¬ 
mental principles now understood could be established 
through research in pure science. It is very much the 
same as in manufacturing itself where parts or whole 
machines can now be made because of improved tools. 
So, in science, laws and principles must first be estab¬ 
lished before we have tools with which to overcome 
problems which up to that time were thought incap¬ 
able of solution. It was not until science and engi¬ 
neering provided the cement gun that we were able to 
make reservoirs and dams sufficiently water tight, nor 
could repairs in clay retorts be made with such 
facility and certainty previous to the development of 
this same device. The principle of the phase-rule 
diagram may be compared with this, and one victory 
which can be credited to this principle was that in the 
manufacture of optical glass where data assembled on 
the principle of the phase rule diagram enabled scien¬ 
tists to demonstrate their independence of secret 
methods and technique, and to calculate the necessary 
components of a complex silicate mixture, so that the 
finished product would come within one or two actual 
trials of having the desired refractive index, specific 
gravity, dispersion and other constants. 

The lack of scientific control frequently spells disas- 


10 


HOW TO CONSERVE MATERIAL 


ter, and a man who fails to appreciate its significance 
cannot hope to progress. I know of fewer better illus¬ 
trations of the penny-wise-pound-foolish practice than 
the case of the man who sought to make potassium 
salts from silicates at a time when potash was selling 
around $400 per ton. Working with a felspar he was 
able to fuse a mass which had a certain small percen¬ 
tage of potash available and this when ground was 
useful as a fertilizer material, supplying potash and 
acting as a filler simultaneously. This fused product 
was sold on a guaranteed basis of available potash, 
and to come up to this guaranty it was necessary to 
analyze the raw materials, to obtain proper propor¬ 
tions and to know accurately the amount of available 
potash in the finished product. That is perfectly 
obvious, and yet because for some weeks the raw 
materials happened to be fairly constant in their 
values the manufacturer thought to save the few dol¬ 
lars cost of the analysis and dispensed with chemical 
assistance. It took him just three weeks to pile up 
and to ship enough material, which failed to meet the 
specifications, to bankrupt the entire enterprise and 
put him permanently out of business. 

In working to specifications it is just as important 
from the money making standpoint not to give too 
much as it is not to give enough. There are very few 
instances where a manufacturer cannot afford to give 
something for good measure, but there has been many 
a case where due to a lack of accurate knowledge 
obtained by scientific methods an excess value was 
given in order to be sure that specifications would be 
met. 


HOW TO CONSERVE MATERIAL 


11 


Conservation Through Electrical Research. —It is 

fascinating to consider how many new devices have 
been developed to make possible new accomplishments 
in industrial conservation. We might divide our sub¬ 
ject according to apparatus and be surprised to learn 
how many are the fields in which they find successful 
application. The electric furnace is an example. Not 
only does it make it possible to produce alloy steels of 
uniform quality, but it enables the manufacturer to 
save expensive ingredients which under other methods 
of melting volatilize and oxidize to a cosiderable 
extent. The electric furnace also makes it possible to 
produce in large quantity the quality of special steels 
which in the olden days was exclusively the product 
of the small crucible. Such a device affords the 
advantages of qualitative production and quantitative 
in that we are learning how to control the reactions 
taking place with a degree of accuracy comparable to 
that employed in making an exact quantitative chemi¬ 
cal analvsis. Much of the waste in metal works, in- 
eluding such dirty materials as foundry sweepings, 
can be fed into the electric furnace and the metallic 
values recovered for use again. In fact, electricity is 
one of our best servants in industrial conservation. 
Electric refining has made it possible to utilize the 
complex zinc ores at Trail. As is well known the 
finest copper required for our electrical machinery is 
refined with a maximum of purity and a minimum of 
loss by electrolytic methods. It is by electrolytic 
methods also that gold and silver are refined with the 
greatest economy, and various compounds of lead 
such as worn out battery plates sometimes find their 



12 


HOW TO CONSERVE MATERIAL 


way back to the metallic state for re-use through re¬ 
fining methods involving the use of electricity. 

In one of the New England valleys where the pro¬ 
duction of brass in its various forms is a leading 
industry, so much metal found its way into the waste 
waters that the waters of the river were aseptic. Salts 
of copper are often used as poisons, but one can 
hardly afford to render aseptic a large body of flowing 
water. This condition having been brought to the 
attention of the manufacturers electrolvtic method 
were devised whereby the metal could be stripped 
from the outgoing water at a very considerable profit. 
Another outstanding application of electricity is the 
recovery of values by the Cottrell precipitation pro¬ 
cess. This, in brief, depends upon the use of a uni¬ 
directional electric current flowing between an elec¬ 
trode which is very efficient in the discharge of 
currents and another which is equally efficient in 
attracting to it such a discharge. The experiment^ of 
recent have shown us that electricity is in fact com¬ 
posed of innumerable tiny bits which have been ca]led 
electrons. If a stream of fine particles, let us 
dust, is carried through such an electrical field, 
small particles making up the electric currents haje a 
tendency to fasten themselves on the bits of dust 
which are thus attracted to one of the electrodes 
where, the currents having been discharged, they 
either cling to the electrode or fall in a mass. Th s is 
the principle of the Cottrell Precipitator; and while 
it seems simple when stated thus, it is in fact a com¬ 
plicated technical device which involves the study of 
the volume, the time, and the temperature, as well as 



say 

the 







HOW TO CONSERVE MATERIAL 


13 


the character of the dust to be precipitated to make 
it applicable in its various fields. The use of this 
precipitator has resulted in real industrial conserva¬ 
tion, for in such a case as the cement plant at River¬ 
side, California, the dust thus separated from the 
stack gases has been found to carry enough potash to 
pay for the operation of the plant; while at the same 
time extensive litigation formerly carried on between 
surrounding farmers and the cement company has 
been made a thing of the past. There is no longer 
any dust to settle upon the countryside and stifle 
vegetation. 

No doubt much of the fame which has been won by 
ibis and other methods of waste prevention has been 
due to the tremendous amount of waste to be recov¬ 
ered. However, this in no wise detracts from the 
value of such methods, for values running into the 
hundreds of dollars per day, if not thousands, have 
Inen won from waste gases and fumes in more than 
Die plant. In other locations such volumes of waste 
materials can be recovered by this method as to 
enbarrass the manufacturer in the disposition of these 
by-products. The statement has been made that in 
oie of the great smelters enough arsenic could be 
recovered from waste gases to make its storage and 
disposition a greater problem than it is now in allow¬ 
ing its discharge into the air. 

Conservation in Metal Extraction. —The introduction 
ol the cyanide process made it possible to separate 
gdd and silver from ores which up to that time had 
yelded to no process for the separation of these 
netals. For years potassium cyanide was the salt 


14 


HOW TO CONSERVE MATERIAL 


employed and great quantities of potash, so necessary 
in agriculture and in the arts, was thus really wasted, 
for we now know that sodium cyanide will do as well. 
Isn’t it strange how long it sometimes takes to learn 
these economies in industrial conservation? These 
delays are often due to prejudices which have no 
foundation in scientific fact, many of them being due 
to insistent advertising on the part of those interested 
in furthering the sale of a particular material. 

A new era in the conservation of metal values in 
tailings, mine dumps, and low grade ores began with 
the introduction of the ore flotation process, concern¬ 
ing which we still know much less than is obviously 
desirable. Bubbles and films are being employed t<j 
treat thousands of tons of low grade material, and ii 
the ore flotation process we have another example c£ 
how a method devised for one purpose may find a use¬ 
ful and important application in a distinctly different 
field. I have in mind work done at the Bureau »f 
Standards in cooperation with the Navy upon the use 
of ore flotation to reduce the total ash content in cap¬ 
tain coals, making them far more adaptable to spechl 
applications. 

Applied Conservation: Fuel. —Closely allied to ill 
metal interests is the fuel problem daily becoming 
more acute throughout the world. It was the ideapf 
compacting more available heat units into restricted 
bunker capacity that turned the attention of the cl- 
loid chemist to the problem of so combining coal wih 
oil as to produce a suspension which may be fired \j 
the usual oil-burning methods. This called for tie 
development of a colloidal fuel which has become a 






HOW TO CONSERVE MATERIAL 


15 


reality. Tlie next step lias been the problem of find¬ 
ing ways to use any fuel oil and many low grade com¬ 
bustible materials which of themselves are unsatis¬ 
factory as sources of heat and power. This comprises 
peat, waste wood, low grade lignite, culm and waste 
resulting from the classification of anthracite and 
bituminous coal. If such materials can be brought 
into colloidal form and suspended in fuel oil the day 
when fuels shall become painfully scarce will be 
indefinitely postponed. 

Another interesting field of research where metals 
and fuel overlap is in the briquetting of all types of 
fine particles. Briquetting is not new, but many of its 
applications are novel, and research in the field of bri¬ 
quetting is sure to effect decided gains in industrial 
conservation. It is well known that punchings and 
various scraps of sheet metal from manufacturing 
operations are remelted and that for some types of 
metals a size of scrap is reached below which it is un¬ 
profitable to endeavor to remelt the material. This is 
due to the oxidization and volatization of these scraps. 
A solution for this difficulty has been found in bri¬ 
quetting, where many sizes and shapes of scrap are 
compressed into suitable masses which can be fed into 
the crucible, the blast furnace, and the hearth. Even 
steel is now briquetted at the rate of many tons per 
hour in some plants. As for fuel, we are becoming 
familiar with the round-cornered cubical briquette 
originally composed of anthracite screenings and a 
suitable binder. As the differential between this type 
of fuel and the familiar anthracite and bituminous 
lumps becomes greater we will see much more briquet- 


16 


HOW TO CONSERVE MATERIAL 


ted fuel used. It seems a simple task to mix such 
material with coal-tar pitch and pass it between rolls 
machined with depressions which match and form the 
briquette, but as a matter of fact the problem differs 
with nearly every material to be used and affords an 
opportunity for research in the development of binders 
that is indeed attractive. Some fuels require pre¬ 
treatment to make them suitable for briquetting, and 
at the present time, Canada is investigating the possi¬ 
bilities of carbonizing the lignites of the middle west 
and then briquetting, with a suitable binder, the coke¬ 
like residue which will be removed from the retorts. 

Waste Paper.—The baling of waste paper, now 
practiced on a large scale, is somewhat analagous to 
briquetting, for it brings into a form easy to trans¬ 
port and handle the waste material which has been 
commonly burned to get it out of the way. The 
mounting prices for all grades of paper makes it 
advisable to burn none of it, but to conserve it and 
direct it back into channels of trade, where as raw 
material it is useful in producing some type of a sheet 
of fibre. The preparation of this waste paper to make 
it suitable for high grade pulps has in itself constitu¬ 
ted a definite research problem. De-inking paper 
constituted a problem that has been pretty well solved, 
but anv treatment must take into consideration varie- 
ties of sizing and filling materials that have come to 
be used in an effort to provide the lithographer and 
the printer with a surface capable of yielding the 
desired effects. 

Copper, Lead, Zinc.— A few statistics will be help¬ 
ful in emphasizing the commercial basis upon which 



HOW TO CONSERVE MATERIAL 


17 


waste metals are recovered. In the tables of the geo¬ 
logical survey such metals are designated as secondary 
metals. Secondary copper, including that in alloys 
other than brass, equalled about 29 per cent of the 
refinery output of primary copper—that is, new metal 
in the United States from all sources—and 37 per cent 
of such metal recovered from domestic ores. This 
quantity is 122,510 tons and was produced by refin¬ 
ing plants working upon new metal as well as those 
dealing in second-hand materials. A large percentage 
of this secondary material originated from the manu¬ 
facture of copper and brass articles and was turned 
over to dealers in part payment for new material. 
Remelted brass amounted to 328,000 tons and second¬ 
ary lead to 41,146 tons. Recovered lead and alloys 
amounted to 55,954 tons. The main sources for this 
secondary lead is old pipe and cable, materials from 
acid chambers and tanks, and worn out batteries. It 
is interesting to note that many toys, heretofore 
imported, used a considerable quantity of impure lead 
scrap. There are two smelters in New Jersey, two in 
New York, and one in California, which work entirely 
upon zinc drosses. There is active competition for 
this class of waste, and the demand for scrap steel has 
led to the de-galvanizing of old zinc-coated scrap, 
thus rendering the sheet steel available. The zinc so 
recovered finds its way to market as carbonate or 
sulphate. 

Tin. —Prominent among the metals recovered on a 
large scale is tin, which results from detinning tin 
plate scrap. There are three processes in general use, 
one involving the use of chlorine, another electrolytic 



18 


HOW TO CONSERVE MATERIAL 


alkali, and the third, alkali saltpeter. The chlorine 
method depends upon the separation of the iron and 
tin by the fractional distillation of their chlorides. 
The scrap to be treated is heated to a temperature 
which brings about a vigorous reaction when chlorine 
is passed over the metal, whereupon both the tin and 
iron are volatilized as chlorides. Sometimes the scrap 
is melted and the chlorine passed through the metal 
held in a Bessemer Converter or some other type of 
suitable furnace. The metallic chlorides thus obtained 
are separated by fractional distillation. The tin chlor¬ 
ide is converted into the oxide or the metal, while the 
iron is recovered finally as pure iron, chlorine gas 
being likewise recovered in a form to be utilized. 

A more universal method of recovering the tin is m 
the form of tetrachloride, largely used for weighting 
silk. In a single year as much as 5,000 tons of tin in 
the form of tetrachloride has been used in the United 
States by the silk industry, and when the conservation 
of tin became important, during the war, steps were 
taken to be sure that those practicing the weighting 
of silk made full recoveries of the metal from spent 
liquors. The electrolytic alkali method gives the tin 
in the form of a sponge precipitate, which is remelted 
into pig tin, and the alkali-saltpeter method recovers 
the tin as an oxide, which is either reduced to the 
metal in a reverberatory furnace or, as the oxide, finds 
useful application in the enameling industry. 

The cans which form the raw material * for this 
industry are collected in the great centers principally 
by contractors who sort the waste of the cities as it 
passes along a picking belt. Some of the tin recovery 


HOW TO CONSERVE MATERIAL 


19 


plants separate tlieir raw material into scrap tin plate 
and old cans. The cans are washed with alkali and 
then briquetted into bales which are placed in drums 
and then treated with chlorine. More than 25,000 tons 
of old cans are treated each year, but the continuation 
of this industry on the present scale is doubtful in 
view of the increasing cost of labor required for sort¬ 
ing out the cans and preparing them for treatment. 
Perhaps the household may officially be called upon to 
assist in this phase of conservation by segregating the 
tin mass in the first instance, so that they may be col- 
lected in course of handling the city’s garbage and 
and laid down at the detinning plant at as low a cost 
as possible. In considering the recovery and use of 
secondary tin it should be remembered that practically 
all of our tin comes from abroad, and that it is a com¬ 
paratively high priced metal. The research worker is 
always tempted by the possibility of finding a cheaper 
material that will prove satisfactory as a substitute 
for tin and thereby reduce the cost of solder-bearing 
metals and several of the important alloys. 

Aluminum, Nickel.—Another of the important metals 
recovered from scrap is aluminum. Much of this metal 
is used directly by foundries in preparing such alloys 
as a Standard No. 12, which must contain at least 92 
percent of aluminum, the balance being copper. Re¬ 
covered aluminum or secondary aluminum will analyze 
something over 98 percent aluminum, and the other 
metals which are likely to be present are copper, steel, 
iron and manganese. Another alloy into which second¬ 
ary aluminum enters in quantity is one containing, 
in addition to aluminum, 4 percent of zinc and 8 per- 


20 


HOW TO CONSERVE MATERIAL 


cent of copper. It will be seen then that this field is 
another in which scientific control of raw materials 
and prices makes possible decided economies through 
the use of cheaper metal mixtures which answer the 
purpose. 

Nickel is another example of metal recovered on a 
commercial scale. This material goes into alloy steel 
and originates in monel metal, nickel, silver, and old 
nickel anodes from electro-plating. 

Metallic Silver. —The difference in the appearance of 
a metal in an unusual physical state, as compared with 
its ordinary condition, has occasionally led to indus¬ 
trial losses. An example is the precipitation of metal¬ 
lic silver on glass surfaces in the production of high 
grade mirrors. This silver is usually precipitated as 
metal from a hydroxide solution from which it is 
separated from the oxygen by some reducing agent. 
Metallic silver in so fine a state of subdivision as is 
the precipitate under these conditions, looks like noth¬ 
ing else so much as mud and has been given that 
name in plants where considerable quantities originate. 
This drab colored material has often been allowed to 
run down the sewers, the management being under 
the impression that the material was worthless. Hav¬ 
ing a large surface in comparison with its weight this 
material may easily float away and in its recovery 
devices have been arranged to hasten its precipitation. 
It is not difficult to prepare either metallic silver or 
the nitrate from this mud and to use it subsequently 
on other mirrors. In this connection it might be 
pointed out that in recent years scientists have learned 
how to so control the deposition of this silver as to 




HOW TO CONSERVE MATERIAL 


21 


produce a larger percentage of first grade work in the 
first instance, also methods for eliminating pinholes in 
the silver film on the mirror and ways of having the 
silver precipitate uniformly and slowly, as well as 
completely, from the solution, thereby conserving the 
time of the operatives and expensive materials. Re¬ 
search has been directed as much toward this factor 
of saving the time of operatives as it has in conserv¬ 
ing materials. The two are often bound up together. 

High-Speed Tools.—We are beginning to appreciate 
tnat it would be desirable to maintain a high scale of 
wages for labor, but that in order to do so it will be 
necessary for labor to produce more in a given unit of 
time or for a given unit of payment than is now the 
case. This can sometimes be done by such improve¬ 
ments as has been given industry through the produc¬ 
tion of high speed tools. 

The operation of tools at high speed, particularly 
where metals are concerned, is accompanied by the 
production of temperatures which are almost sure to 
destroy the temper of the tool and rapidly wear 
down the cutting edge. A corps of scientists have 
been constantly at work upon this problem, and their 
success has been enough to afford great encourage¬ 
ment. The problem involves improvements in metals, 
improvements in machines which drive the tools, and 
in better cooling and lubricating mediums. It has 
been found that a plant equipped with carbon steel 
tools becomes immediately capable of producing 
approximately three times as much work in the same 
length of time with the same mechanical equipment 
and the same operatives if the modem tungsten tool 




22 


HOW TO CONSERVE MATERIAL 


steel is installed. These tools can be driven three 
times as fast or three times as far in the same unit of 
time as the older type of tool without being deformed 
or greatly changed in the increased heat. That con¬ 
stitutes the whole story. Tungsten steel is now being 
crowded for first honors by other alloys, such as the 
one comprised of cobalt, chromium and tungsten. 
There are those who claim that this newer alloy is 
150 percent as efficient as the tungsten steel, and it is 
known that the new alloy performed very creditable 
service under the pressure of the war emergency. 

Machining Operations. —The research laboratory, in 
cooperation with the plant using the electric furnace, 
has also developed steel which retains its dimensions 
and shape when hardened, and it therefore becomes 
possible to produce by punch and die methods parts 
would otherwise have to be machined. This is because 
some intricate dies cannot be fashioned from pre¬ 
hardened steel, and yet they cannot perform their 
duties unless they are hardened. The advantage is 
therefore apparent when a steel is produced of a soft¬ 
ness to allow machining and of a character to allow 
hardening without deformation. Die casting is 
another example where science has come to the aid of 
industry and effected conservation in industry through 
the saving of time, which is money. Extrusion is 
another modern method, and electric welding has 
opened up a new field because of its superiority for 
some purposes over acetylene, or gas welding, or the 
thermit process, which is so efficient where large 
masses of metal are required in addition to the weld¬ 
ing itself. 






HOW TO CONSERVE MATERIAL 


23 


Welding. —Welding effects considerable economies 
daily, and in sheet metal work has made possible per¬ 
fectly satisfactory products which could not have been 
put together so well or so rapidly if bolts, screws, 
rivets or soldering had been used. Spot welding has 
been developed to the place where a perfect union of 
metals can be depended upon, and by employing elec¬ 
trodes of various peculiar shapes nearly any condition 
can be met. The success of this type of electric weld¬ 
ing has encouraged research to the point where weld¬ 
ing interests have come together in a society which is 
directing its efforts toward learning the best processes 
for particular work and improved practices without 
regard to furthering any particular process. 

One of the most striking examples of the service 
which welding can render is to be found in the repair 
of German merchant ships which were in American 
harbors. It was largely through welding and the re¬ 
pairs made possible by employing welding apparatus 
that these vessels could be put into service in months 
as compared with the years reckoned by those respon¬ 
sible for the attempted destruction of the special 

machinery. 

•/ 

Electro-plating. —Electro-plating has been another 
factor in industrial conservation. The principle not 
only is used to coat a baser metal with something 
designed either to improve its wearing qualities or 
protect it, but has also been applied in metal clean¬ 
ing, the stripping of base metals and in making a type 
of etching. Research has devised ways for speeding 
up electro-plating, both by devising baths in which 
plating can be carried on in a fraction of the time 


24 


HOW TO CONSERVE MATERIAL 


formerly required, and also in the design of mechan¬ 
ical devices for the plating of small articles without 
the necessity of wiring each individual piece, as was 
the former practice. 

Metal Coating. —While speaking of metal coatings 
the introduction of compressed air in connection with 
spraying devices for japanning and lacquering must 
he mentioned, for they have done as much toward 
giving a more uniform coating as any other improve¬ 
ment. At the same time the element of time saved is 
not inconsiderable. There has always been a certain 
tire hazard in japanning and lacquering, and one of 
our research laboratories directed its efforts toward 
lessening that hazard, the primary interest being to 
make safe the use of special ovens in which the con¬ 
cern was interested. The effort was successful, and 
lacquers in which the inflammable, volatile solvent is 
replaced by water are now available. This achieve¬ 
ment has been made possible through the application 
of the principles of colloidal chemistry, ways having 
been devised for saponifying the waxes and gums in 
an aqueous medium rather than by dissolving them in 
an inflammable solvent. The conservation effected is 
assured not only by the saving of solvent, but by the 
elimination of the danger of considerable personal in¬ 
jury and property loss involved in the use of more 
dangerous materials. 

Textiles. —In this discussion we have drawn our ex¬ 
amples largely from the metal field, but there are 
other cases equally striking to be found in practically 
every corner of industry. The accurate measurement 
of cotton fibres conducted in a research laboratory 


HOW TO CONSERVE MATERIAL 


25 


disclosed the fact that a certain mill actually spun 
fibres one and one-eighth inch in length, whereas they 
were careful to purchase one and one-quarter inch 
staple. There is a difference in the value of cotton 
fibre, one of the determining factors being the length 
of staple. By changing the setting of the machinery 
it was found possible to eliminate the breaking of the 
fibre, which was responsible for the reduction of one- 
eightli inch in its length, but it was also demonstrated 
in the plant, although inadvertently, that the quality 
of the goods which the mill desired to make could be 
produced from the shorter and somewhat less expens¬ 
ive fibre. 

The textile industry gained enormously when meth¬ 
ods of bleaching by chemical means were devised. 
Formerly all fabric was bleached by being spread 
upon the grass in the sunlight, but today as good a 
job can be done by properly controlled chemical meth¬ 
ods. At one time the reactions involved in this bleach¬ 
ing were not well understood; and in one instance 
where the process was believed to require thirty 
hours for its completion, scientists were able to show 
that by the proper control of temperatures and pres¬ 
sures this reaction could be made to go forward to 
completion in forty-five seconds, thereby effecting a 
saving of fourteen-fifteenths of the capital which was 
necessary for apparatus, labor, and interest on the 
values of the stock in process. 

Corrosion.— Corrosion is one of our worst enemies, 
and great progress will have been made when we can 
successfully combat it in all its phases. Much has been 
learned on the subject, examples being the creosoting 



26 


HOW TO CONSERVE MATERIAL 


of timber for special purposes and the development of 
numerous paints, bituminous coatings, and a variety 
of varnishes, some of which involve the use of syn¬ 
thetic gums and waxes which are products of the lab¬ 
oratory. New alio vs which resist corrosion have been 

e */ 

devised and are extensively used in fittings, valves, 
and for exterior construction, particularly in roofs. 
We have just begun to use sheet zinc as roofing 
material. 

One method of defence has involved rendering the 
corrosive agent less virile in its attack. The experi¬ 
ence of a New York building will illustrate the point. 
It is only in recent years that we have used great 
quantities of aerated water. Such water carries oxy¬ 
gen to iron pipes in a way to promote corrosion, and 
in the building in question it was found that the 
plumbing would soon have to be replaced unless some¬ 
thing was done to retard corrosion. One can well im¬ 
agine the feelings of owners confronted with the ex¬ 
pense of replacing the plumbing, especially under 
present-day conditions, and in view of the fact that 
it was so placed as to make necessary a practical re¬ 
construction of a part of the building. Scientists rea¬ 
soned that if the water could have its appetite for 
iron satisfied before it went into the pipes corrosion 
could be stopped, and this was actually accomplished 
by providing a tank fitted with iron plates and other 
pieces put there to be corroded and easily replaced 
with fresh material when necessary. The saving ran 

v CD 

into many figures. 

Differences Between Success and Failure. —The days 
when rule of thumb methods can be made to answer 



HOW TO CONSERVE MATERIAL 


27 


liave passed for tlie majority of industries. It has 
been pointed out that in many cases the smaller indus¬ 
tries which look upon their larger fellows as those 
particularly favored by circumstances, by large capital 
at their disposition or by some favorite treatment, for 
their success, fail to appreciate that in many instances 
the difference between them is largely a difference in 
the appreciation of how industrial conservation can be 
effected by the consistent, sustained and continued ap¬ 
plication of scientific principles and scientific methods 
to their problems. A few examples have been given 
above of what has been accomplished. This list might 
be extended almost indefinitely, and in many books 
will be found in detail the reactions involved in effect¬ 
ing a certain prevention of waste or waste utilization. 
In many cases a science has to be built up before the 
industry can profit by it. Those industries founded 
upon a science are indeed fortunate, but those who 
have not yet learned from experience the advantages 
which science offers them have encouragement to 
begin their investment in research from what has 
been achieved under the direction of their fellows in 
other fields of endeavor. 






















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